Those are good suggestions, can I also add some thoughts:

• direct messaging system, including group chat functionality inside Steemit (instead of having to go to Discord or Steemit.chat)
• next to 'home', 'new', 'hot', 'trending' and 'promoted' a 'curated' tag, where posts appear that have been selected by different curating groups (like curie, whalepower, PAL, minnowbooster, etc)
• Ability to sub-categorize your feed, make different lists of people you follow so you can have a specific feed for for example"funny accounts", "photographers", "steemit developers", etc. When you are following more than 200 people, the feed really becomes disorganized. (Twitter has this feature, called Twitter lists, it's a life saviour for me)